JUNE 2018 OBSERVING
Sun, Moon & Planets by Fred Schaaf
To find out what's
visible in the sky
from your location,
go to skypub.com/
almanac.
Planets Aplenty
The planets are out in full force this month, and they are joined by an asteroid.
S
aturn is at opposition, visible virtually all night long this month, as
is the asteroid Vesta, shining slightly
brighter than it has in decades. Venus is
at its highest this year for mid-northern
latitude observers after sunset. Mercury is much lower than Venus but still
relatively high in evening twilight by
month's end. Jupiter is visible almost
all night long and still near its brightest. Mars, just one month away from
perihelic opposition, rises in the late
evening and ﬂames up by a whole magnitude to rival Jupiter's brightness by
the end of June.
DUSK AND EVENING
more than 15″, and its phase decreases
from 80% to 70%. The bright lights
of Gemini, the stars Castor and Pollux, twinkle above Venus as twilight
deepens. Venus is about 5° lower left of
Pollux on June 5-9. On the American
evenings of June 19th and 20th, Venus
is on the outskirts of M44, the Beehive
Star Cluster in Cancer.
Mercury is at superior conjunction
with the Sun on the night of June 5-6
but emerges into visibility low in the
dusk by mid-month. By month's end
Mercury sets 1½ hours after the Sun,
dimming to a little brighter than 0.1
magnitude. It also grows to 6½″ wide
and thins to less than 2/3 lit. Greatest
elongation will occur on July 12th.
Venus attains its highest sunset altitude of the year on June 6th at almost
28° for observers around latitude 40°
DUSK TO DAWN
north. The planet starts the month setJupiter is already visible in the southting more than 2½ hours after the Sun,
east at nightfall during June and is
but the interval is some 15 minutes
highest around 11 p.m. local time as the
shorter before the
month is over.
Moon
Venus brightens
Moon
June 3
from magnitude
June 2
Mars
Moon
-3.9 to -4.1 in
June 1
June. Its apparent
diameter increases
Saturn
Dawn, June 1 - 3
from about 13″ to
month begins and 9 p.m. as it ends. The
giant planet dims from magnitude -2.5
to -2.3 during June, and its angular
diameter decreases from 44″ to 41½″.
But this is still prime observing season
for Jupiter (see pages 50-51 for details
about viewing the Galilean moons and
the Great Red Spot). The huge world
continues to drift westward relative to
the stars of Libra in June.
ALL NIGHT
Saturn comes to opposition on June
27th, only half a day before the full
Moon poses around 1° upper left of
Saturn. Saturn brightens from magnitude +0.2 to +0.0 in June. Its globe is a
little more than 18″ across. The glorious
rings span a distance about 2½ times
greater than the globe and are tilted
25.7° to our line of sight, almost the
maximum possible. This month is the
best for trying to see special Saturnian
Dusk, June 8
1 hour after sunset
Pollux
1 hour before sunrise
u These scenes
are drawn for near
the middle of North
America (latitude 40°
north, longitude 90°
west); European observers should move
each Moon symbol
a quarter of the way
toward the one for the
previous date. In the
Far East, move the
Moon halfway.
46
Castor
Venus
S A G I T TA R I U S
GEMINI
10°
Procyon
Looking South
J U N E 2 018 * SK Y & TELESCOPE
Looking South-Southwest
Looking West-Northwest